Association between foetal sex and adverse neonatal outcomes in women with gestational diabetes.

AIMS: Foetal male sex is associated with adverse perinatal outcomes. However, studies evaluating the impact of foetal sex on perinatal outcomes in women with gestational diabetes (GDM) are scarce. We studied whether male new-born sex is associated with neonatal outcomes, in women with GDM. METHODS: This is a retrospective study based on the national Portuguese register of GDM. All women with live-born singleton pregnancies between 2012 and 2017 were eligible for study inclusion. Primary endpoints under analysis were neonatal hypoglycaemia, neonatal macrosomia, respiratory distress syndrome (RDS) and neonatal intensive care unit (NICU) admission. We excluded women with missing data on the primary endpoint. Pregnancy data and neonatal outcomes between female and male new-borns were compared. Multivariate logistic regression models were built. RESULTS: We studied 10,768 new-borns in mothers with GDM, 5635 (52.3%) male, 438 (4.1%) had neonatal hypoglycaemia, 406 (3.8%) were macrosomic, 671 (6.2%) had RDS, and 671 (6.2%) needed NICU admission. Male new-borns were more frequently small or large for gestational age. No differences were observed on maternal age, body mass index, glycated haemoglobin, anti-hyperglycaemic treatment, pregnancy complications or gestational age at delivery. In the multivariate regression analysis, male sex was independently associated with neonatal hypoglycaemia [OR 1.26 (IC 95%: 1.04-1.54), p = 0.02], neonatal macrosomia [1.94 (1.56-2.41), p < 0.001], NICU admission [1.29 (1.07-1.56), p = 0.009], and RDS [1.35 (1.05-1.73, p = 0.02]. CONCLUSIONS: Male new-borns have an independent 26% higher risk of neonatal hypoglycaemia, 29% higher risk of NICU admission, 35% higher risk of RDS, and almost twofold higher risk of macrosomia, compared to female new-borns.

Maternal height as a predictor of glucose intolerance in the postpartum and its relationship with maternal pre-gestational weight.

PURPOSE: Short stature predicts higher risk of developing type 2 diabetes. We studied the association between height and glucose intolerance in women with gestational diabetes mellitus (GDM) and whether this association differed according to body mass index (BMI). METHODS: Retrospective study of the Portuguese GDM registry. EXCLUSION CRITERIA: missing data on postpartum oral glucose tolerance test (OGTT) or BMI. ENDPOINT: postpartum glucose intolerance (diabetes mellitus or prediabetes on the 6-8 weeks postpartum OGTT). Women were divided by mean height and compared. A multivariate logistic regression was used, and the analysis was stratified by BMI (cut-off: 30 kg/m2) and interaction was tested. RESULTS: We included 7402 women; mean height was 161.9 ± 6.2 cm. Taller women had lower BMI and lower rates of glucose intolerance (6.8 vs. 8.8%, p = 0.002). Women with BMI < 30 kg/m2 were taller than those with obesity. Height associated with glucose intolerance. The multivariate adjusted OR of glucose intolerance was 0.98 (95% CI 0.96-0.99), p = 0.001, per 1 cm increase in height. This association was only observed in women with BMI < 30 kg/m2: OR 0.97 (95% CI 0.95-0.99), < 0.001. There was no such association in women with BMI ≥ 30 kg/m2: OR 0.99 (95% CI 0.97-1.02), p = 0.65. P for interaction between BMI and height was 0.09. CONCLUSIONS: In non-obese pre-gestational women, height is inversely associated with postpartum glucose intolerance. Per 1 cm increase in height, women present a 3% decrease in the risk of developing diabetes mellitus or prediabetes.

First trimester fasting glucose and glycated haemoglobin cut-offs associated with abnormal glucose homeostasis in the post-partum reclassification in women with hyperglycaemia in pregnancy.

Hyperglycaemia first detected during pregnancy is either gestational diabetes mellitus (GDM) or previous undiagnosed diabetes. We aimed to study if there were a first trimester fasting glycaemia (FTG) and a glycated haemoglobin (HbA1c) cut-off values associated with type 2 diabetes mellitus (T2DM) or abnormal glucose homeostasis (AGH) at the post-partum oral glucose tolerance test (OGTT) reclassification. We retrospectively studied a group of pregnant women from the Portuguese National Registry of GDM. Receiver-operating characteristic (ROC) curves were used to determine the best FTG and HbA1c cut-offs to predict T2DM and AGH. We studied 4068 women. The area under the ROC curves (AUC) for the association with T2DM was 0.85 (0.80-0.90) for FTG and 0.85 (0.80-0.91) for HbA1c. The best FTG cut-off for association with T2DM was 99 mg/dL: sensitivity 77.4%, specificity 74.3%, positive predictive value (PPV) 4.8%, and negative predictive value (NPV) 99.5%. The best HbA1c cut-off for association with T2DM was 5.4%: sensitivity 79.0%, specificity 80.1%, PPV 5.7%, and NPV 99.6%. The AUC for the association of FTG and HbA1c with AGH were 0.73 (0.70-0.76) and 0.71 (0.67-0.74), respectively. The best FTG cut-off for predicting AGH was 99 mg/dL: sensitivity 59.4%, specificity 76.2%, PPV 17.0%, and NPV 95.8%. The best HbA1c cut-off was 5.4%: sensitivity 48.7%, specificity 81.5%, PPV 17.8%, and NPV 95.1%. We suggest an FTG of 99 mg/dL and an HbA1c of 5.4% as the best cut-offs below which T2DM is unlikely to be present. Almost all patients with FTG < 99 mg/dL and HbA1c < 5.4% did not reclassify as T2DM. These early pregnancy cut-offs might alert the physician for the possibility of a previous undiagnosed diabetes and alert them to the importance of testing for it after delivery.

Development and internal validation of a clinical score to predict neonatal hypoglycaemia in women with gestational diabetes.

INTRODUCTION: Gestational diabetes (GD) is a risk factor for neonatal hypoglycaemia (NH), but other factors can increase this risk. OBJECTIVES: To create a score to predict NH in women with GD. METHODS: Retrospective study of women with GD with a live singleton birth between 2012 and 2017 from the Portuguese GD registry. Pregnancies with and without NH were compared. A logistic regression was used to study NH predictors. Variables independently associated with NH were used to score derivation. The model's internal validation was performed by a bootstrapping. The association between the score and NH was assessed by logistic regression. RESULTS: We studied 10216 pregnancies, 410 (4.0%) with NH. The model's AUC was 0.628 (95%CI: 0.599-0.657). Optimism-corrected c-index: 0.626. Points were assigned to variables associated with NH in proportion to the model's lowest regression coefficient: insulin-treatment 1, preeclampsia 3, preterm delivery 2, male sex 1, and small-for-gestational-age 2, or large-for-gestational-age 3. NH prevalence by score category 0-1, 2, 3, 4, and ≥5 was 2.3%, 3.0%, 4.5%, 6.0%, 7.4%, and 11.5%, respectively. Per point, the OR for NH was 1.35 (95% CI: 1.27-1.42). A score of 2, 3, 4, 5 or ≥6 (versus ≤1) had a OR for NH of 1.67 (1.29-2.15), 2.24 (1.65-3.04), 2.83 (2.02-3.98), 3.08 (1.83-5.16), and 6.84 (4.34-10.77), respectively. CONCLUSION: Per each score point, women with GD had 35% higher risk of NH. Those with ≥6 points had 6.8-fold higher risk of NH compared to a score ≤1. Our score may be useful for identifying women at a higher risk of NH.

Metformin combined with insulin in women with gestational diabetes mellitus: a propensity score-matched study.

AIM: Metformin use in gestational diabetes (GDM) is a common practice. Although its use in combination with insulin might be advantageous, it was never formally tested. We studied whether combined treatment was associated with better obstetric or neonatal outcomes compared to insulin alone. METHODS: This is a retrospective study, using the Portuguese National Registry of GDM (2012-2017), of women treated with insulin ± metformin. Primary endpoints were obstetric and neonatal complications. Secondary endpoints were gestational weight gain (GWG) and insulin dose. A propensity score-matched analysis was performed to balance the distribution of age, BMI, insulin treatment duration, HbA1c, first trimester diagnosis of GDM and previous GDM or macrosomia. Women treated with metformin plus insulin and insulin only were then compared. RESULTS: A total of 4034 women were treated with insulin or insulin plus metformin (10.2%). After propensity score matching, we studied two groups of 386 patients. Obstetric and neonatal complications were similar. Women treated with metformin plus insulin had 201 (52.1%) obstetric complications versus 184 (47.7%) in insulin-only group, p = 0.22; and 112 (29.0%) neonatal complications versus 96 (24.9%), p = 0.19. Patients treated with metformin plus insulin had similar GWG, excessive weight gain and insulin dose compared to the insulin-only group. CONCLUSIONS: Women with GDM treated with insulin plus metformin had similar obstetric and neonatal complications, weight gained and insulin dose compared to those only treated with insulin.